In an indoor environment, a satellite signal is weak while arriving at the ground and cannot penetrate through a building; therefore, satellite positioning cannot be used for positioning. But in practical application, positioning in the indoor environment, i.e., indoor positioning, is needed frequently, so as to facilitate indoor position management, monitoring or tracking, etc., for example, positioning shelves in a supermarket and an emporium, or the like; positioning or tracking positions of indoor devices in an electronic map; and implementing interaction between indoor electronic devices by mutually positioning the positions thereof, etc.
Among indoor positioning technologies at current, technologies like Wi-Fi, Bluetooth, infrared rays, ultra-wideband, RFID, ZigBee or ultrasound technology or the like are adopted usually to implement indoor positioning by using signal intensities transmitted among the devices. Specifically, the intensity of a signal transmitted between a target device with a position to be determined and a plurality of known devices with known positions is converted into a device distance between the target device and the known devices, so that the position of the target device can be calculated.
However, signal intensity errors may be caused by signal interference and design differences in antennas, circuits and housing of devices under different brands, which will lead to inaccurate position of the target device acquired.